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Servicing valve gear > < Removing cylinder head

A4 Cabriolet Mk2

Checking compression
   
Checking compression
Special tools and workshop equipment required
t  Compression tester -V.A.G 1763-
t  Spark plug socket and extension -3122 B-
t  Puller -T40039-
t  Spring type clip pliers -VAS 5024 A-

Test sequence
  Note
t  Engine oil temperature at least 30 °C
t  Battery voltage at least 12.7 V
   
–  Pull off engine cover panel -arrows-.
  A10-10292
–  Remove bolts -1-.
–  Unplug electrical connectors -2- from ignition coils and move wiring clear.
  A15-0699
–  Remove ignition coils with output stages -2- using special tool -T40039-.
–  Remove spark plugs with spark plug socket -3122 B-.
–  Unplug 8-pin connector for injectors → Anchor.
–  Check compression pressure with compression tester -V.A.G 1763- and adapter -V.A.G 1763/6-.
  Note
Using the compression tester → Operating instructions.
–  Operate starter until pressure reading on tester no longer rises.
Compression pressure:
  A15-0700
New pressure in barWear limit in bar Permissible difference between cylinders in bar
11.0 ... 14.07.03.0 (maximum)

–  Install spark plugs → Booklet803.
–  Install ignition coils → Rep. Gr.28.
–  Read out fault memory of engine control unit → vehicle diagnostic, testing and information system VAS 5051 in the "Guided Fault Finding" function.
  Note
Faults will have been stored in the memory because connectors have been unplugged. Interrogate and, if necessary, erase fault memory after completing the check.
   

Servicing valve gear > < Removing cylinder head